• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.20 no.2
• /
• pp.173-177
• /
• 2007

Electro-wetting display (EWD) that displays information by controling movement of fluid is one of the strong candidates for electronic paper display (EPD). In EWD cell. the movement of oil which locates between hydrophobic insulation layer and deionized water is rather random, which makes it difficult to realize gray scale, fast response time, and good color characteristics. In this paper, we investigated how to control the oil movement in specific one direction by surface treatment and pattered electrodes. From these experiments, we could control oil movement in a desired direction.

• The KSFM Journal of Fluid Machinery
• /
• v.18 no.6
• /
• pp.27-30
• /
• 2015

In this study, we attempted to harvest energy using water droplet based on Reverse Electro Wetting On Dielectric (REWOD) phenomenon between water droplet and dielectric surface without external bias. REWOD device can be fabricated via simple coating process, which is highly economic and easy. We believe that our system is well-suited for IoT(Internet of Things) embedded electronics that require low but consistent electricity. Moreover, our device can be integrated with window to generate electricity upon raindrops.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2004.08a
• /
• pp.1220-1222
• /
• 2004

We developed a new device structure using anisotropic phase separation from liquid crystal (LC) and polymer composite materials using UV intensity variation and polymer wetting properties. In the device, the LC molecules are isolated in pixels where LCs are surrounded by the inter-pixel vertical polymer walls and the horizontal polymer films on the upper substrate. These devices show very good mechanical stability against external pressure. The electro-optic characteristics and the mechanical stability of the devices are discussed in view of the flexible display applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.286-287
• /
• 2006

Electrowetting display (EWD) is one of the strong candidates for electronic paper like display (EPD). However, in the conventional EWD, the oil movement occurs in random direction so that we can observe irregular distribution of contracted oil in the operation. To realize colorful display and achieve a fast response time, oil movement in the pixel should be directed in a specific direction. In this paper, we report the result of oil contraction with specified direction which is achieved by patterned electrode. From the experiments, we find that the oil movement depends on the portion of etched electrode area and study other influencing factors of patterned electrode on the oil movement.

• Journal of Information Display
• /
• v.7 no.2
• /
• pp.12-15
• /
• 2006

We propose a patterning method of liquid crystal (LC) alignment layer for producing multi-domain LC structures. By controlling thermal conditions during micro-contact printing procedures and facilitating wetting properties of patterning materials, patterned LC orientation can be easily obtained on a bare ITO surface or other polymer films. The newly proposed patterning method is expected to be a very useful tool for fabricating multi-domain LC structures to enhance or design electro-optic properties of LC-based devices.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2010.05a
• /
• pp.20.2-20.2
• /
• 2010

Recently inkjet printing technology has been developed in the areas of low cost fabrication in environmentally friendly manufacturing processes. Although inkjet printing requires the interdisciplinary researches including development of materials, manufacturing processes and printing equipment and peripherals, manufacturing a printhead is still core of inkjet technology. In this study, a piezoelectric driven DOD (drop on demand) inkjet printhead has been fabricated on three layers of the silicon wafer in MEMS Technology because of its chemical resistance to industrial inks, strong mechanical properties and dimensional accuracy to meet the drop volume uniformity in printed electronics and display industries. The flow passage, filter and nozzles are precisely etched on the layers of the silicon wafers and assembled through silicon fusion bonding without additional adhesives. The piezoelectric is screen-printed on the top the pressure chamber and the nozzle plate surface is treated with non-wetting coating for jetting fluids. Printheads with nozzle number of 16 to 256 have been developed to get the drop volume range from 5 pL to 80 pL in various industrial applications. Currently our printheads are successfully utilized to fabricating color-filters and PI alignment layers in LCD Flat Panel Display and legend marking for PCB in Samsung Electronics.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2008.10a
• /
• pp.1286-1289
• /
• 2008

We report on a wide-viewing liquid crystal (LC) display with bi-level microstructures spontaneously formed by selective wetting on a chemically heterogeneous surface. The bi-level microstructures serve as spacers for maintaining uniform cell gap, as well as protrusions for wide-viewing properties. Our LC cell having the bi-level microstructures shows good electro-optic properties.